In the discussion that follows, reference is made to certain structures and/or methods. However, the following references should not be construed as an admission that these structures and/or methods constitute prior art. Applicants expressly reserve the right to demonstrate that such structures and/or methods do not qualify as prior art.
Instruments of many different configurations are known. For example, certain types of instruments control experiments or collect information from an environment or unit or material(s) under test. By way of example only, such instruments include digital multimeters, oscilloscopes, DNA sequencers, pressure sensors, temperature sensors, pH sensors, or the like.
Historically, instrumentation has developed from the use of discrete instruments that are dedicated to a single function and manually operated, such as a centrifuge or spectrophotometer, to instrumentation systems that integrate multiple processes. Such multiple process instruments typically require complicated or multi-step procedures be manually performed by a user to operate the individual instruments. In some cases, discrete instrument systems have been combined and automated in an effort to reduce costs and increase productivity. Examples of such combined instruments include the integration of large liquid handling robotic workstations. FIG. 1 illustrates a block diagram of an exemplary system 100 having a fully reusable instrument 110 that contains all operational components (e.g., user interface, CPU/control systems, detector systems, process controllers, fluid handling, data storage, and power module).
To reduce sample cross contamination, the fixed sample handling components of some instruments, such as the plumbing and fluid containers, have been replaced in many applications with disposable components, such as plastic tubing, well plates, and centrifuge tubes.
Increasing interest in the development of micro-scale systems for the integration of instrumentation components has been brought about by the many advantages of miniaturisation. In particular, performance improvements can be achieved over traditional laboratory equipment in terms of automation, reproducibility, speed, cost and size.
Polymer-based microfluidic components have been developed as a cost effective alternative to silicon for simple, disposable components in instrumentation systems. However, these systems have been limited in complexity and the degree of integration because they involve externally driven fluid-handling components, sensors, and actuators. U.S. Pat. Nos. 6,900,889, 6,810,713 and 6,408,878, and U.S. Patent Application Publications 2004/209354A and 2002/0148992A1 illustrate implementations of such systems. FIG. 2 illustrates a block, diagram of an exemplary system 200 that includes a reusable instrument 210, containing all operational components (e.g., user interface, CPU/control systems, detector systems, process controllers, data storage, and power module) except for fluid-handling components, which are located on a removable consumable device 205.
Polymer-based microfluidic devices which incorporate on-board sensors and actuators that interface to external instrumentation have also been developed, such as those described in U.S. Pat. Nos. 6,073,482, 6,896,778 and 6,103,033. The limitations of such devices include reliability, problems relating to the interface to connectors and problems associated with long interconnects (e.g., electromagnetic interference and susceptibility, line impedance, packaging and device size).
Smart Card polymer devices are known that contain memory modules and, in some cases, central processing units (CPU's) for use in personal identification, security, and payment applications. Examples of such Smart Cards are described in the ISO 7816 and ISO 7501 standards for identification cards, ISO 14443, ISO 10536, and ISO 15693 standards for RFID cards from the International Organization for Standardization, and GSM 11.11 from the Global System for Mobile Telecommunications standard. Smart Cards can be classified according to the type of chip they contain and type of interface they use to communicate with an external instrument. Generally, there are three different types of chips associated with Smart Cards grouped according to the functionality they provide, including memory-only, wired logic, and microcontroller based Smart Cards.
Memory-only Smart Cards include serial protected memory cards. Such cards provide for data storage capabilities, in a manner similar to magnetic stripe cards, but have greater data storage capacity and can be used with a lower cost reading device than magnetic-based cards. Memory-only Smart Cards do not contain logic or perform calculations, however, and simply store data with some cards also having data protection features.
Wired-logic Smart Cards contain a logic-based state machine that provides encryption and authenticated access to card memory and its contents. Wired-logic Smart Cards have a static file system supporting multiple applications, with optional encrypted access to memory contents, but the command set and file structure associated with these cards can only be changed by redesigning the integrated circuit (IC) on the card. FIG. 3 illustrates a block diagram of an exemplary system 300 that includes an instrument 310, which interfaces with a Chip Card 305, containing logic and data storage.
Microcontroller Smart Cards, commonly referred to as “Smart Cards,” contain a microcontroller with an operating system. The microcontroller executes logic, performs calculations and stores data in accordance with its operating system and on-board memory can be updated many times. FIG. 4 illustrates a block diagram of an exemplary system 400 that includes an instrument 410, which interfaces with a Smart Card 405, containing a CPU and data storage.
All of these types of Smart Cards require an external instrumentation interface to operate that can be categorised as a contact or contact-less interface depending on how the electrical connection is implemented. Smart Cards may offer both types of interfaces by using two separate chips (sometimes called “hybrid cards”) or a dual-interface chip.
Smart Cards with internal power supplies are known, and thin film batteries for such cards are currently being developed. Smart Cards with internal power supplies have been described for memory storage, such as for backup applications. For example, U.S. Pat. No. 6,854,657 describes a twin battery configuration for field programmable Smart Cards allowing the use of volatile memory.
Smart Card devices for autonomous operation are also known. For example, “Super Smart Cards” that incorporate graphical user interface (GUI) and interactive elements have been demonstrated and generally incorporate microprocessor, memory, battery, liquid crystal display (LCD) and membrane keypad components. Although these devices show increased functionality over the standard Chip and Smart Cards, none have been demonstrated with sensor or actuator control or with fluidic component integration.
Smart Cards with on-board biometric fingerprint sensor interfaces are known for use in some security applications. For example, U.S. Pat. No. 6,848,617 describes a fingerprint sensor module for insertion into a Smart Card, and U.S. Pat. No. 6,325,285 describes a Smart Card containing memory, microprocessor, input/output (I/O) and fingerprint biometric sensor components. International Patent Application Publication WO00161638A1 describes a more generic Smart Card for biometric sensing that is interfaced to internal or external sensors for measuring data, but because the device includes no provisions for actuator operation or sensor control or feedback, the device functionality is limited to basic sensor data acquisition.
U.S. Pat. No. 6,454,708 describes another example of a Smart Card operating as part of a sensor system. The Smart Card is interfaced to an electrocardiogram (ECG) device on a patient such that ECG data is collected and stored on the card before transporting the card to an external instrument for monitoring and processing. This configuration is limited in that it applies to ECG data measurement only and, even though some of the interface electronics may be placed on-board the card, the card only stores the acquired ECG data.
Additionally, U.S. Pat. No. 6,896,778 describes using a blank Smart Card chip carrier module with an electrode having a semipermeable membrane in direct contact with an internal fluidic channel. However, this device does not provide for any on-chip electronics or integrated circuits interfaced to sensor or actuator components, allowing for only very limited automation and integration with an external instrument. U.S. Patent Application 2005/0031490 describes a sensor chip on a smart card electrode module, wherein the silicon sensor chip contains its own integrated electrode array with multiplexer and amplifier, and the sensor chip is encapsulated to have the sensitive area exposed to fluid and its electrical connections associated with the smart card electrode module. Although, like U.S. Pat. No. 6,896,778, the system described in U.S. Patent Application 2005/0031490 is still limited to this single architecture of the sensor chip directly connected to the smart card interface.
Low-cost disposable Radio Frequency Identification (RFID) labels, called “Smart Labels,” have been incorporated with sensor circuits for monitoring purposes. For example, U.S. Patent Application Publication 2005/0088299 describes an RFID based sensor network, which acquires sensor data wirelessly through a reader and communicates with another instrument for processing the data, and U.S. Patent Application Publication 2005/174236 describes an RFID system, which comprises a transceiver, sensor system, and interface to identify, track and acquire the operational history of a product-during its life cycle. Both of these device configurations are limited in operation to responding to an external reader, which interrogates and provides power to the RFID sensor systems, and to providing only sensor and RFID data for processing by the external system. Further, U.S. Patent Application Publication 2005/0248455 describes an RFID sensor system that is limited to monitoring time and temperature to determine the freshness, or shelf life, of perishable items. While this device can periodically reactivate from a low power state to perform a monitoring function, it still requires communication to an external device upon interrogation.
Memory components have been incorporated into polymer-based microfluidic components for instrumentation systems, in which full control and monitoring are provided by an external instrument. FIG. 5 illustrates a block diagram of an exemplary instrumentation system 500 containing all operational components (e.g., user interface. CPU/control systems, detector systems, process controllers, and power module), except for fluid-handling components, which are located on a removable consumable device 505 with data storage capability.
For example, U.S. Patent Application Publication 2004/0248318 describes a removable biochip on a chip card with read/write-able memory, but provides no direct interface between the fluid or on-chip sensors or actuators. Thus, this configuration performs only a memory operation, and the fluidic component must be removed for processing with external instruments. Similarly, U.S. Pat. No. 6,153,085, U.S. Patent Application Publications 2002/155033A1 and 2005/0019213, and International Patent Application Publications WO 2003/082730A and WO 2004/112946 describe microfluidic systems incorporating memory components, but these devices are limited in that they incorporate only memory-based circuit components and include no self-operation capability and no electronic sensor or fluidic system interface on the device. Thus, such devices must operate interfaced with external instruments and are therefore limited by the associated interconnect problems. Further, such devices cannot perform autonomous or even semi-autonomous operations and provide no sensor and/or actuator monitoring, control, feedback, or signal enhancement.